title: Evaluating the specificity of a new type of urine collection bag for infants.
abstract: OBJECTIVE
  For diagnosing urinary tract infection (UTI) in infants, the urine collection bag is a common sampling method. It has several advantages versus other methods but a high risk of contamination makes culture results difficult to evaluate. Previous studies report a specificity ranging from 14% to 84%. The objective of this study was to evaluate the specificity of a new type of urine collection bag.
  
  
  METHODS
  Urine samples were collected from healthy infants with a new type of collection bag. As the urine is expected to be sterile, any bacterial growth would be considered a contamination.
  
  
  RESULTS
  Forty-four samples were included: 40 samples showed <10,000 cfu/ml of mixed growth or no growth at all, three samples showed <10,000 cfu/ml of single-strain growth and one sample showed >10,000<100,000 cfu/ml of single-strain growth. No samples showed any growth >100,000 cfu/ml.
  
  
  CONCLUSIONS
  According to Kass criteria, 97.7% of the samples would exclude a UTI and 2.3% would be considered inconclusive. None of the samples had a contamination level that, falsely, would be interpreted as positive. Further studies will be valuable as a specificity of 97.7% suggests that this collection device could give the clinician a non-invasive option for diagnosing UTI in infants.
authors.affiliation: Department of Pediatrics, Hospital of Helsingborg, Lindahls v. 9, 260 83 Vejbystrand, Sweden.
authors.forename: Markus
authors.initials: M
authors.lastname: Perlhagen
authors.forename: Thomas
authors.initials: T
authors.lastname: Forsberg
authors.forename: John
authors.initials: J
authors.lastname: Perlhagen
authors.forename: Michael
authors.initials: M
authors.lastname: Nivesjö